When out on a holiday in Rome, car rental is actually not necessary but if you insist, you might end up paying too expensive an amount. You can make arrangement yourself, or go through your hotel’s concierge.
There are car rental services available in the airport once you reach the city. Rome’s major highways are easily accessible and maps are available. If you really intend to drive around the city, be sure to consider familiarizing yourself with the maps first. Be warned about how you will surely encounter heavy traffic.
You can also consider renting a scooter since that is one of the easiest ways to tackle the streets of Rome. A car or taxi may not be your wisest choice for fast transit around especially if you don’t have much time but you want to cover a lot of grounds.